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1.
Psychol Assess ; 35(2): 152-164, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455027

RESUMO

One of the most commonly replicated results in the research area of recidivism risk assessment is the superiority of structured and standardized prediction methods in comparison to unstructured, subjective, intuitive, or impressionistic clinical judgments. However, the quality of evidence supporting this conclusion is partly still controversially discussed because studies including direct comparisons of the predictive accuracy of unstructured and structured risk assessment methods have been relatively rarely conducted. Therefore, we examined in the present study retrospectively N = 416 expert witness reports written about individuals convicted of violent and/or sexual offenses in Germany between 1999 and 2015. The predictive accuracy of different methodological approaches of risk assessment (subjective clinical [i.e., unstructured clinical judgment; UCJ], structured professional judgment [SPJ], actuarial risk assessment instruments [ARAIs], and combinations of ARAIs-/SPJ-based risk assessments) was compared by analyzing the actual reoffenses according to the Federal Central Register (average follow-up period M = 7.08 years). In accordance with previously published results, the results indicated a higher predictive accuracy for structured compared to unstructured risk assessment approaches for the prediction of general, violent, and sexual recidivism. Taken together, the findings underline the limited accuracy of UCJs and provided further support for the use of structured and standardized risk assessment procedures in the area of crime and delinquency. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Reincidência , Delitos Sexuais , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Comportamento Sexual , Medição de Risco/métodos
2.
J Biol Chem ; 284(5): 2598-2602, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-19004816

RESUMO

Several neurological diseases, including Parkinson disease and dementia with Lewy bodies, are characterized by the accumulation of alpha-synuclein phosphorylated at Ser-129 (p-Ser-129). The kinase or kinases responsible for this phosphorylation have been the subject of intense investigation. Here we submit evidence that polo-like kinase 2 (PLK2, also known as serum-inducible kinase or SNK) is a principle contributor to alpha-synuclein phosphorylation at Ser-129 in neurons. PLK2 directly phosphorylates alpha-synuclein at Ser-129 in an in vitro biochemical assay. Inhibitors of PLK kinases inhibited alpha-synuclein phosphorylation both in primary cortical cell cultures and in mouse brain in vivo. Finally, specific knockdown of PLK2 expression by transduction with short hairpin RNA constructs or by knock-out of the plk2 gene reduced p-Ser-129 levels. These results indicate that PLK2 plays a critical role in alpha-synuclein phosphorylation in central nervous system.


Assuntos
Sistema Nervoso Central/metabolismo , Proteínas Quinases/metabolismo , Serina/metabolismo , alfa-Sinucleína/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Sistema Nervoso Central/enzimologia , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Proteínas Serina-Treonina Quinases , Interferência de RNA , alfa-Sinucleína/química
3.
Traffic ; 9(7): 1116-29, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18419754

RESUMO

The cellular prion protein (PrP(c)) is a glycosyl-phosphatidylinositol (GPI)-anchored protein trafficking in the secretory and endocytic pathway and localized mainly at the plasma membrane. Conversion of PrP(c) into its pathogenic isoform PrP(Sc) is associated with pathogenesis and transmission of prion diseases. Intramolecular cleavage in the middle, the extreme C-terminal part or within the GPI anchor and shedding of PrP(c) modulate this conversion process by reducing the substrate for prion formation. These phenomena provide similarities with the processing of amyloid precursor protein in Alzheimer's disease. Sorting nexins are a family of proteins with important functions in protein trafficking. In this study, we investigated the role of the newly described sorting nexin 33 (SNX33) in trafficking and processing of PrP(c). We found that overexpression of SNX33 in neuronal and non-neuronal cell lines resulted in increased shedding of full-length PrP(c) from the plasma membrane and modulated the rate of PrP(c) endocytosis. This was paralleled by reduction of PrP(Sc) formation in persistently and newly infected cells. Using deletion mutants, we demonstrate that production of PrP fragment N1 is not influenced by SNX33. Our data provide new insights into the cellular mechanisms of PrP(c) shedding and show how this can affect cellular PrP(Sc) conversion.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Príons/química , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/fisiologia , Amiloide/química , Animais , Biotinilação , Encéfalo/metabolismo , Proteínas de Transporte/química , Linhagem Celular , Linhagem Celular Tumoral , Endocitose , Deleção de Genes , Humanos , Camundongos , Modelos Biológicos , Doenças Priônicas/metabolismo , Príons/metabolismo , Transporte Proteico , Nexinas de Classificação , Proteínas de Transporte Vesicular/química
4.
J Biol Chem ; 283(21): 14257-68, 2008 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-18353773

RESUMO

Ectodomain shedding of the amyloid precursor protein (APP) by the two proteases alpha- and beta-secretase is a key regulatory event in the generation of the Alzheimer disease amyloid beta peptide (Abeta). beta-Secretase catalyzes the first step in Abeta generation, whereas alpha-secretase cleaves within the Abeta domain, prevents Abeta generation, and generates a secreted form of APP with neuroprotective properties. At present, little is known about the cellular mechanisms that control APP alpha-secretase cleavage and Abeta generation. To explore the contributory pathways, we carried out an expression cloning screen. We identified a novel member of the sorting nexin (SNX) family of endosomal trafficking proteins, called SNX33, as a new activator of APP alpha-secretase cleavage. SNX33 is a homolog of SNX9 and was found to be a ubiquitously expressed phosphoprotein. Exogenous expression of SNX33 in cultured cells increased APP alpha-secretase cleavage 4-fold but surprisingly had little effect on beta-secretase cleavage. This effect was similar to the expression of the dominant negative dynamin-1 mutant K44A. SNX33 bound the endocytic GTPase dynamin and reduced the rate of APP endocytosis in a dynamin-dependent manner. This led to an increase of APP at the plasma membrane, where alpha-secretase cleavage mostly occurs. In summary, our study identifies SNX33 as a new endocytic protein, which modulates APP endocytosis and APP alpha-secretase cleavage, and demonstrates that the rate of APP endocytosis is a major control factor for APP alpha-secretase cleavage.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas de Transporte/metabolismo , Endocitose , Proteínas de Transporte Vesicular/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Proteínas de Transporte/química , Linhagem Celular , Chlorocebus aethiops , Clonagem Molecular , Dinaminas/metabolismo , Regulação Enzimológica da Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Fosforilação , Ligação Proteica , Transporte Proteico , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Nexinas de Classificação , Transferrina/metabolismo , Proteínas de Transporte Vesicular/química
5.
Int J Dev Neurosci ; 24(2-3): 141-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16446073

RESUMO

Ectodomain shedding of the amyloid precursor protein (APP) is a key regulatory step in the generation of the amyloid beta peptide (Abeta), which is thought to provoke the pathogenesis of Alzheimer's disease. To better understand the cellular processes that regulate ectodomain shedding of APP we used human embryonic kidney 293 cells and applied a sib-selection expression cloning approach. In addition to a known activator of APP shedding -- protein kinase A -- the following cDNAs were identified: the endocytic proteins endophilin A1 and A3, the metabotropic glutamate receptor 3 (mGluR3), palmitoyl-protein thioesterase 1 (PPT1), Numb-like and the kinase MEKK2. Endophilins A1 and A3, as well as mGluR3 activated APP shedding relatively specifically. They had little or no effect on the shedding of the unrelated membrane proteins TNF receptor 2 and P-selectin glycoprotein ligand-1. In contrast, MEKK2 and PKA also increased shedding of TNF receptor 2, suggesting that these kinases contribute to a general program regulating ectodomain shedding. The strongest activator of APP shedding, endophilin A3, reduced the rate of APP endocytosis and specifically increased APP shedding by the protease alpha-secretase, as measured in an antibody uptake assay and by immunoblot analysis. This suggests that endophilin A3 is a novel modulator of APP trafficking affecting access of APP to alpha-secretase. In summary, this study shows that expression cloning is a suitable way to identify proteins controlling ectodomain shedding of membrane proteins.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Expressão Gênica/fisiologia , Aciltransferases/metabolismo , Precursor de Proteína beta-Amiloide/genética , Western Blotting/métodos , Linhagem Celular , Clonagem Molecular/métodos , Proteína Quinase Tipo II Dependente de AMP Cíclico , Endocitose/fisiologia , Ativação Enzimática/fisiologia , Biblioteca Gênica , Proteínas de Fluorescência Verde/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , Processamento de Proteína Pós-Traducional , Transporte Proteico/fisiologia , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fatores de Tempo , Transfecção/métodos , Transferrina/metabolismo
6.
J Biol Chem ; 281(11): 7583-94, 2006 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-16344553

RESUMO

Ectodomain shedding of the amyloid precursor protein (APP) is a key regulatory step in the generation of the Alzheimer disease amyloid beta peptide (Abeta). The molecular mechanisms underlying the control of APP shedding remain little understood but are in part dependent on the low density lipoprotein receptor-related protein (LRP), which is involved in APP endocytosis. Here, we show that the APP homolog APLP1 (amyloid precursor-like protein 1) influences APP shedding. In human embryonic kidney 293 cells expression of APLP1 strongly activated APP shedding by alpha-secretase and slightly reduced beta-secretase cleavage. As revealed by domain deletion analysis, the increase in APP shedding required the NPTY amino acid motif within the cytoplasmic domain of APLP1. This motif is conserved in APP and is essential for the endocytosis of APP and APLP1. Unrelated membrane proteins containing similar endocytic motifs did not affect APP shedding, showing that the increase in APP shedding was specific to APLP1. In LRP-deficient cells APLP1 no longer induced APP shedding, suggesting that in wild-type cells APLP1 interferes with the LRP-dependent endocytosis of APP and there by increases APP alpha-cleavage. In fact, an antibody uptake assay revealed that expression of APLP1 reduced the rate of APP endocytosis. In summary, our study provides a novel mechanism for APP shedding, in which APLP1 affects the endocytosis of APP and makes more APP available for alpha-secretase cleavage.


Assuntos
Precursor de Proteína beta-Amiloide/química , Motivos de Aminoácidos , Secretases da Proteína Precursora do Amiloide , Precursor de Proteína beta-Amiloide/fisiologia , Animais , Ácido Aspártico Endopeptidases , Western Blotting , Células CHO , Células COS , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Citoplasma/metabolismo , Endocitose , Endopeptidases/metabolismo , Deleção de Genes , Genes Reporter , Vetores Genéticos , Humanos , Imunoprecipitação , Microscopia de Fluorescência , Modelos Genéticos , Peptídeos/química , Plasmídeos/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química , Fatores de Tempo , Transfecção
7.
EMBO Rep ; 5(6): 620-5, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15167888

RESUMO

The aspartyl protease BACE1 has a pivotal role in the pathogenesis of Alzheimer's disease. Recently, it was shown that in Alzheimer's disease patients, BACE1 levels were elevated although mRNA levels were not changed compared with controls. Here, we demonstrate that the 5'-untranslated region (5'UTR) of BACE1 controls the rate of BACE1 translation. In the presence of the 5'UTR, we observed more than 90% reduction of BACE1 protein levels in HEK293, COS7 and H4 cells, and a similar reduction of BACE1 activity in vitro. mRNA levels were not affected, demonstrating that the 5'UTR repressed the translation but not the transcription of BACE1. The 3'UTR did not affect BACE1 expression. An extensive mutagenesis analysis predicts that the GC-rich region of the 5'UTR forms a constitutive translation barrier, which may prevent the ribosome from efficiently translating the BACE1 mRNA. Our data therefore demonstrate translational repression as a new mechanism controlling BACE1 expression.


Assuntos
Regiões 5' não Traduzidas/genética , Doença de Alzheimer/enzimologia , Ácido Aspártico Endopeptidases/genética , Regulação Enzimológica da Expressão Gênica , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide , Animais , Ácido Aspártico Endopeptidases/análise , Ácido Aspártico Endopeptidases/biossíntese , Sequência de Bases , Regulação para Baixo , Endopeptidases , Humanos , Dados de Sequência Molecular , Mutação , Fases de Leitura Aberta/genética , Biossíntese de Proteínas/genética , RNA Mensageiro/análise , RNA Mensageiro/metabolismo
8.
Mol Microbiol ; 52(4): 1091-105, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15130127

RESUMO

The Bacillus subtilis sigma(W) regulon is induced by different stresses such as alkaline shock, salt shock, phage infection and certain antibiotics that affect cell wall biosynthesis. The activity of the alternative, extracytoplasmic function (ECF) sigma factor sigma(W) is modulated by a specific anti-sigma factor (RsiW or YbbM) encoded by the rsiW (ybbM) gene located immediately downstream of sigW. The RsiW membrane topology was determined, and a specific reporter system for RsiW function was constructed. Experiments using the yeast two-hybrid system suggested a direct interaction of sigma(W) with the cytoplasmic part of RsiW. Analysis of truncated forms of the RsiW protein revealed that sigma(W) induction by alkaline shock is dependent on both the transmembrane and the extracytoplasmic domain of RsiW. Western blot and pulse-chase experiments demonstrated degradation of RsiW after an alkaline shock. A B. subtilis mutant strain deleted for the Escherichia coli yaeL orthologue yluC, encoding a transmembrane protease, was defective in inducing a sigma(W)-controlled promoter after alkaline shock and accumulated a membrane-bound truncated form of RsiW, suggesting that the activity of sigma(W) is controlled by the proteolysis of RsiW by at least two different proteolytic steps.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Fator sigma/antagonistas & inibidores , Transcrição Gênica , Fusão Gênica Artificial , Proteínas de Bactérias/genética , Western Blotting , Deleção de Genes , Genes Reporter , Concentração de Íons de Hidrogênio , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Regulon , Deleção de Sequência , Técnicas do Sistema de Duplo-Híbrido , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
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